Lubrication system



Dec. 27, 1932. A ANDRAKE 1,892,931

LUBRICATION SYSTEM Filed Aug. 31. 1927 INVENTOR.

Andrew A. Andrake A TTORNE Y.

Patented Dec. 27, 1932 STATES mama earsa'r Fries" ANDREW A. ANDRAKE, 0F CLEVELAND, OHIO, ASSIG NOR TO GLENN L. MARTIN COMPANY, OF CLEVELAND, OHIO, A CORPORATION OF OHIO LUBRICATION SYSTEM Application filed August 31, 1927. Serial No. 216,560.

This invention relates to improvements in lubricating systems for internal combustion engines used for the propulsion ofaircraft.

The quiet, eflicient and satisfactory running of an internal combustion engine is dependent, amongst other things, upon lubrication. The physical characteristics of lubricating oil change greatly with temperature, and as no enginecan be designed to have maximum efficiency and smooth running under all of the various conditions which may be encountered, it follows that at various times there must be inefliciency and lack of smooth running unless corrective means are provided.

The object of my invention is to overcome the difficulty above mentioned by the provision of means for controlling oil temperature in such a way that the oil in an engine maybe brought up to the proper temperature quickly at the time of starting the engine, and may be maintained substantially at a temperature best adapted to conditions encountered at different altitudes throughout any running period.

Another object is the provision of means under control of the operator from his usual position in the aircraft for regulating the temperature of the oil.

Another object is the provision of a radiator in a system of this character for cooling the oil which is circulating therethrough together with manual means for short circuiting the radiator, and also means for regulating the effectiveness of the radiator by manually varying the flow of air therethrough.

Another object is to cushion the pressure of oil in an engine oil circulating system to thus relieve the radiator tubes of abruptly changing pressures due to sudden accelera tion of the pump, or to pulsations of the pump, or to excessive stresses caused by abnormally high viscosity of the oil.

Another object is the provision of means for passing heated air through the radiator and through tubes surrounding oil pipesin the system, whereby the raising of the oil temperature may be accomplished before starting-the engine.

Another object is to provide means for simultaneous closure of an air inlet and of an air outlet of a radiator to thus maintain fluidity of the oil contained therein under low temperature conditions, and to facilitate efficient pre-heating of the oil.

Other objects and features of novelty will appear as I proceed with the description of that embodiment of the invention which, for the purposes of the present application, I have illustrated in the accompanying drawing, in which i Fig. 1 is a view in perspective, largely diagpammatic in character, illustrating a part of the lubricating system of an internal combustion engine located outside of the engine casing;

Fig. 2 is a perspective view of a heater which may be employed in carrying out certain features of the invention, and

Fig. 3 is a plan view of a pair of shutter doors which I may employ for regulating the eflectiveness of the radiator.

Similar reference characters refer to like parts throughout the views.

In the drawing a fragment of a crank case of an internal combustion engine is illustrated at 10, while the casing of an oil circulating pump is shown at 11 connected with the bottom of the crank case. The present invention is not concerned with the details of the oil pump, which may be of any suitable design so long as it is adapted to take oil from the engine, pass it through a circulating system outside of the engine and then return it to the engine for re-use. By means of such pump the oil that has been heated by use in the engine is caused to leave the same through a pipe 12 and travel into the top of a storage tank 13 which is located upon the aircraft at a point above the level of pump 11. From the bottom of tank 13 a pipe 14 leads downwardly to a radiator 15 which I prefer to form somewhat elongated in a horizontal direction and to mount upon the vehicle with its long dimension parallel to the direction of movement of the vehicle. In effect, the radiator consists of an outer shell and a large number of tubular element-s forming air passages within the shell, the spaces between the tubes being closed and soldered up at each end only. Shrouds 16 and 17 en- :lose the ends of the radiator, these shrouds being tapered somewhat so that the entire unit comprising radiator and shrouds approximates more or less closely a streamlined body. v v 4 At their free ends the shrouds 16 and 17 have circular openings 18 and 19, in each of whichI mount a pair of semi-circular shuttain fuel, preferably in the form of paste,-

for example, the so-called solid alcohol which is procurable in small cans to fit within the cup 25. Over the top of the latter I may mount a wire gauze 26 for confining the flame. A suitable bracket 27 is attached to the shroud 16 for removably supporting the cup 25.

The pipe 14 passes through the top .of the shell of the radiatornear the rear end of the latter so as to deliver oil by gravity from the tank 13 to the interior of the radiator. Outside the radiator the pipe 14 is connected by a union 28 with a pipe 29 running parallel to the radiator and having connection at its forward end through a union 3O with"a pipe 31, the lower end of which extends into the radiator and the upper end of which is connected with the pump casing" 11'. Thevalve casing 32 is interposed between portions of pipe 29 and contains a shut-off valve which may be opened or closed by the rota tionof a stem- 33. A shaft 34 provided with a handle 35 located within the reach of the Qperator when occupying his normal position is employed for rotating stem 33 through the intermediacy of bevel pinions 36. Means are also provided for moving the rod 24 from a position convenient to the operator. As shown herein this is accomplished by a crank 37 mounted on the lowerend of arock shaft 38 and pivotally connected with the rod 24. The upper end of shaft 38 is provided with an'operating handle 39 which may have a pointer thereon movable over the face of a dial 40 provided with markings to indicate the various adjustments of the shutter doors- 20 and 21.

A casing 41, which is roughly semi-cylindrical in shape, encloses pipe 29. This cas-' ing extends somewhat beyond the ends of the radiator 15 and has a flanged lower edge which is attached to the radiator and to the shrouds 16 and 17. Openings .42 and 43 through the shrouds16 and 17 respectively,

serve to connect the spaces within the shrouds to the space within the casing 41. This casing merges into tubes 44 and 45 surrounding the pipes 14 and 31, respectively, these pipes being open at their upper ends.

In the drawing the flow of oil is indicated by solid line arrows, while the flow of air 1s indicated by broken line arrows.

Operation-JVhe'n an engine equipped with my invention is to be started, the fuel in cup 25 is ignited and the cup is mounted in bracket 27. The shutter doors 20 and 21 are heat is transferred from the air to the oil either through the walls of the radiator tubes or through the walls of pipes 14 and 31. The size of hole 42 may be varied to control the proportion of heated air that shall passthrough that opening and through the radiator tubes, and, if desired, the hold 42 may -be omitted entirely so that all of the heated air must traverse the radiator.

The heater 25 may be caused to function for a time before the engine is started with the result that a considerable quantityof oil, that is, all that is contained within the radiator 15, is rendered warm and fluid, while that contained within the pipes 14 and 31 is also heated to a greater or lesser extent. Consequently from themoment the engine is usual difficulty in starting, in so far as it is caused by cold lubricant, is avoided. As further oil flows into the radiatogto take the place of that drawn into the en ine, this oil temperature may rise above the maximum which is considered desirable. The pilot thenmoves handle 39 toopen shutter doors 20 and 21, more or less, thereby permitting the motion of the aircraft to draw cool air through the radiator 15, by which means some of the heat is absorbed from the oil. On the other hand, should low temperature conditions be encountered, as where an aircraft rises to a great height, and the oil consestartedit is supplied with warm oil, and the quently should become too cool for satisfactory operation even with the shutters 20, 21 fully closed, the operator may then turn han-v dle 35 to open the valve in the by-pass pipe 29 whereupon the oil is free to move directly from pipe H to pipe 31 without passing through the radiator 15, and thus very little of the heat absorbed by the oil from the engine is lost in the circulating system outside the engine, with the result that the temperature of the whole body of oil in the system' gradually rises. Hence it will be observed that the use of my invention enables the operator to adjust the oil temperature in accordance with atmosphere temperature and altitude conditions as visually indicated to him by his instruments and as his judgment dictates.

While I have described the invention with more or less particularity and have shown the same somewhat in detail in the appended drawing, it should be understood that such detail disclosure is employed for purposes of illustration and is not to be construed as limiting the invention except Where such details are specifically included within the appended claims. I

Having thus described my invention, I claim:

1. In a lubricating system for vehicle engines, an oil pipe in'said system located outside of the engine, a tube enclosing a portion of said pipe, one end of said tube being higher than the other, asubstantially closable chamber at the lower end of the tube, and a detachable heating unit having an opening I therethru located in said chamber.

2. In a lubricating system for aircraft engines, means for regulating the temperature of engine oil comprising aradiator and bypass combination unit having an inlet and an outlet; a reserve oil'pressure supply tank outside said engine cooperating with said radiator unit to cool said oil; manually operable means associated with said imit for proportioning flow of oil through the by-pass of saidunit to thereby affect the rate of oil How through said radiator; means operated by the engine for delivering oil from said engine to said tank; a gravity flow pipe from said tank to said radiator and by-pass unitinlet, and

p a return flow pipe from-said radiator and pass unit outlet to said pump. K

In an aircraft engine lubricating system, a longitudinally disposed oil cooling radiator comprising in combination a stream lined shell; passages within said shell for air and for oil; means for connecting said oil passages to said system; a bifurcated shutter, the half portions of said shutter geared together for simultaneous movement in one direction, and means under control of an operator for operation of said shutter.

.5. In an aircraft engine lubricating system, a longitudinally disposed oil cooling radiator comprising in combination a streamlined shell; passages within said shell for air and for oil; means for connecting said oil ator mounted upon the aircraft in longitudi nal relation, said radiator comprising a tubular shell, air passages and oil passages longitudinally disposed within said shell; and manually operable shutters for the inlet and the outlet of said air passages; a by-pass in said circulating means around saidradiator a valve in said by-pass; and means in proximity to the operators seat for operating said valve and said shutters for controlling the relative flow of oil and air through said radiator.

In testimonywhereof, hereunto aflix my signature.

Aunnnw A. ANDRAKE,

lined shell; passageswithin said shell for air and for oil; means for connecting said oil passages to said system; two shutters, one at each end of saidshell and means under control .of an operator for simultaneous operation-of said shutters.

\ 4. In an aircraft engine lubricating system, a longitudinally disposed oil cooling radiator comprising in combination a stream- 

